This invention relates to an improved accelerator pedal. In particular, this invention relates to an accelerator pedal for electronic control of a vehicle engine having improved hysteresis characteristics.
Automotive engines utilizing electronic throttle control systems are now more common than conventional carbureted engines. In a carbureted engine, the accelerator pedal is connected to the throttle valve by a cable. Depressing the pedal rotates the throttle valve against the action of a return spring. The carbureted engine throttle control has established a certain xe2x80x9cfeelxe2x80x9d for engine speed and acceleration. However, with electronic throttle control systems, a cable connection to the carburetor is no longer required, yet the same xe2x80x9cfeelxe2x80x9d for acceleration is still desired.
U.S. Pat. No. 4,944,269 attempts to address the problem of an accelerator pedal for an electronic which produce sufficient hysteresis to the pedal shaft thereby producing the xe2x80x9cfeelxe2x80x9d of a carbureted engine. This accelerator pedal utilizes three springs and numerous components making such an accelerator pedal relatively expensive to manufacture and assemble.
The disadvantages of the prior art may be overcome by providing an accelerator pedal having minimal of components which produces the desired hysteresis characteristics.
It is desirable to provide an accelerator pedal assembly having a mounting bracket and a pedal arm mounted to the bracket. The pedal arm pivots between an idle position and a full throttle position. A biasing mechanism extends between the pedal arm and the bracket for urging the pedal arm to the idle position. A friction disc engages the biasing mechanism for movement therewith. The friction disc is in frictional engagement with a stationary friction plate for relative movement therebetween. Movement of the pedal arm from the idle position towards the full throttle position responsively rotates the friction disc relative to the friction plate and the biasing mechanism responsively increases frictional engagement between the friction disc and the friction plate by urging the friction disc and friction plate together.
It is desirable to provide an accelerator pedal assembly comprising a mounting bracket, a pedal arm and a biasing mechanism. The arm is pivotally mounted to the bracket for movement between an idle position and a full throttle position. The biasing mechanism comprises a first coil extending between the pedal arm and the bracket, a second coil extending between the pedal arm and the bracket. The first coil engages and responsively rotates a first friction disc against a friction plate which mounted to the bracket. The second coil engages and responsively rotates a second friction disc against the friction plate. The biasing mechanism biases the arm to the idle position. As the arm is rotated towards the full throttle position, frictional resistance to the movement is produced by the first and second friction discs frictionally engaging the friction plate.
It is desirable to provide an accelerator pedal assembly comprising a mounting bracket, a pedal arm and a biasing mechanism. The arm is pivotally mounted to the bracket for movement between an idle position and a full throttle position. The biasing mechanism comprises a first coil extending between the pedal arm and the bracket. The first coil engages and responsively rotates a first friction disc against a friction plate which mounted to the bracket and a second friction disc mounted for frictional rotation relative to the arm. The biasing mechanism biases the arm to the idle position. As the arm is rotated towards the full throttle position, frictional resistance to the movement is produced by the first friction disc frictionally engaging the friction plate and by the second friction disc frictionally engaging the arm.